Making your animations subtle is very important. This usually means they should be very short, circa 300ms or less. However even a tiny amount of undamped spring means they need more time to feel natural.

Perceived smoothness is a function of distance travelled and the frame rate, so the further the total distance travelled (in any direction, e.g. when bouncing on a spring), the longer the animation must be to appear smooth. Even if it is longer than you would normally like such an animation to be.

There is some real gold in the recently posted full interview with Jony Ive and Craig Federighi in Businessweek. If you’re an Apple follower and have read the Jobs biography you will recall that Steve … Read more →